Dairy Food Intake Is Not Associated With Frailty in Adults From the Framingham Heart Study

Abstract

Background: Nutrients, including protein, calcium, and fat may be associated with risk of frailty, yet specific contributions from whole dairy foods rich in these nutrients remain understudied.

Objective: To determine associations between dairy intake (milk, yogurt, cheese, total (milk + yogurt + cheese), low-fat and high-fat dairy, and servings per week) and frailty onset and frailty phenotype components.

Design: Prospective cohort study. All dairy intake exposures (servings per week) were assessed via a food frequency questionnaire.

Participants and setting: Participants (aged 33 to 86 years) from the Framingham Offspring Study who were not frail at baseline (1998-2001) completed a food frequency questionnaire and had 1 or 2 follow-up frailty assessments (2005-2008 and 2011-2014) were included.

Main outcome measures: Frailty was defined as the presence of ≥3 Fried frailty phenotype components: unintentional weight-loss, exhaustion, slowness (gait speed), weakness (grip strength), and low physical activity. Individuals with zero to two components were considered nonfrail.

Statistical analyses performed: Repeated measures logistic regression estimated odds ratios and 95% CIs for frailty onset. Logistic (exhaustion and weight loss) and linear regression (gait speed, grip strength, and physical activity) estimated the association between baseline dairy intake and each frailty component at follow-up, adjusting for baseline values for age, sex, energy intake (residual analysis), current smoking, and multivitamin use. Models were further adjusted for health status in a secondary analysis.

Results: Mean baseline age ± SD was 61 ± 9 years (range = 33 to 87 years), and 54% were women. Of 2,550 nonfrail individuals at baseline, 8.8% (2005-2008) and 13.5% (2011-2014) became frail. Higher yogurt intake was associated with decreased odds of frailty (odds ratio 0.96, 95% CI 0.93 to 0.99; P = 0.02). Each additional serving of yogurt (β ± SE) .004 ± .001; P < 0.01) and low-fat dairy (β ± SE) .001 ± .0006; P = 0.04) was associated with significantly faster follow-up gait speed. Dietary intakes of high-fat dairy were associated with increased odds of frailty (odds ratio 1.02, 95% CI 1.00 to 1.04; P = 0.05), but the P value was of borderline significance. No associations were observed for other dairy foods. After adjusting for health status, the associations of high-fat dairy and yogurt with frailty became nonsignificant, although the magnitudes of the associations did not change. The association between yogurt and gait speed decreased in magnitude after adjusting for health status (β ± SE) .002 ± .001; P = 0.01).

Conclusions: Dietary intakes of yogurt were modestly associated with reduced frailty onset and dietary intakes of high-fat dairy had a borderline association with increased odds of frailty, but other dairy food intakes showed no association in this study of healthy adults. Some dairy food intakes were modestly associated with follow-up gait speed. However, effect sizes were small, and the clinical importance of these associations remains undetermined.

Keywords: Aging; Dairy intake; Frailty; Nutrition; Prospective cohort study.